1. Field of the Invention
This invention relates to a rotary head type recording and reproducing apparatus arranged to be capable of after-recording (post-recording) new information on a recording medium on which a video signal, etc., has already been recorded.
2. Description of the Related Art
Some of known 8-mm type VTRs (video tape recorders) are arranged to be capable of after-recording new information, in addition to an existing record on a recording medium, at a guard band part between a video signal recording area and a PCM (pulse-code-modulated) audio signal recording area within an information recording track to be scanned by a rotary head.
FIG. 1 shows by way of example an information recording track formed on a recording medium by the VTR of the above-stated kind. Referring to FIG. 1, a magnetic tape 1 which is employed as the recording medium moves rightward at a given speed. Information tracks 2 are then formed one after another by means of a rotary head which is not shown. Each of the information tracks 2 is composed of a video signal recording area 3, a PCM audio signal recording area 4 and a new information recording area 5. These recording areas 3, 4 and 5 are independent of each other. Therefore, the recording track arrangement permits after-recording of information.
However, in after-recording new information alone on a magnetic tape which has the existing record of a video signal or a video signal and a PCM audio signal, the new information is controlled to be recorded in the new information recording area 5 which is fixedly set according to the recording format of the magnetic tape 1, irrespectively of the actual recorded positions of the video and PCM audio signals. Therefore, in a case where the recorded position of the video signal or the PCM audio signal happens to be deviating from the recording format, the after-recorded new information might reach the video signal recording area or the PCM audio signal recording area to ruin or destroy in part the existing record of the video or PCM audio signal.